|
Technical
Publications:
Top Ten Questions and
Answers from Customers:
1) What is the Flow Matrix
Device?
a. The Flow Matrix device is a self-regulating
mechanical flow controller that is immune to both inlet and outlet
pressure changes and transients.
Flow Matrix offers manual knob operated, air actuated, electro-mechanical,
and high/low pressure versions of the mechanical flow control
technology. The electronic versions of Flow Matrix technology still
have the
same internal self-regulating mechanisms, but can attain
a user-defined set point electronically. After set point has been
attained, they
do not require the electronics to maintain the flow rate.
All Flow Matrix devices are volumetric control devices fundamentally,
but mass
flow control options can be performed in certain cases.
2) Does Flow Matrix have hazardous area classifications?
a. The Flow Matrix manual and air-actuated
devices do not require hazardous area classifications in the U.S.
and Canada because there
are no electrical components. The electro-mechanical devices
are slated for Class 1, Div 2 (Zone 2) classification in 2005.
If there
is a need for electronically controlled flow control in a
Class 1, Div 1 or 2 zones, Flow Matrix offers a fully closed-loop
air
actuated solution called the Safe-T-Flow Matrix where all
non-classified electronics can be put into a safe zone.
3) What is a pressure-immune flow controller?
a. A pressure immune flow controller,
such as the Flow Matrix devices, can maintain a constant, pre-set
flow rate regardless of pressure
changes on the inlet and outlet of the device (within specified
operational parameters).
4) What are the benefits of using Flow Matrix technology over more
traditional approaches such as regulators/needle valves or
mass flow controllers?
a. Although there are many specific benefits of this approach to
flow control, the general benefits are:
i. Flow Matrix mechanical units self-regulate with changes in inlet or
outlet pressure to keep flow rate constant without human interaction. Pressure
regulators
and needle valve combinations require constant adjustment as process/pressure
conditions change.
ii. Flow Matrix devices can effectively control the
flow of liquids. There is not a wide product offering of liquid control
devices that are cost-effective
for most applications.
iii. Traditional mass flow controllers are highly pressure dependent meaning
that they must have very stable pressure conditions which require additional
pressure regulation devices.
iv. Flow Matrix devices to not have to “hunt” for
set point; meaning that once set, they keep a very stable flow rate. Mass
flow controllers have
to constantly hunt and re-adjust whenever conditions change which leads
to instabilities or long stabilization times.
v. Flow Matrix controllers do not require power to maintain flow rate. Even the
electronic units maintain a stable and constant flow rate when power is removed
from the device.
5) What are the flow-ranges that Flow Matrix devices can control?
a. Standard Flow Matrix products can be ranged
to control anywhere from 5 cc/min up to 3 gal/min of liquid flow (i.e.
water, we can attain higher flows if the
specific gravity is lower than water). For gas flows, we can range the
device anywhere from 20 cc/min up to 110 liters/min of air (can attain
higher flows
for gases that have lower density or viscosity of air). Special low-flow
or low-pressure/vacuum calibrations can be performed for a nominal add-on
charge.
6) What are the pressure
limitations of Flow Matrix devices?
a. The overall pressure limits are a function
of the fluid type and flow rate, but in general, Flow Matrix has solutions
that can operate anywhere from 3500
psig of inlet pressure down to small inlet pressures of 10 psig or less.
Typical operational differentials for all normal gas and liquid applications
is around
15-30 psig, but special accommodations can be met with the proper specifications
provided at time of quotation request. Backpressure (or outlet pressure)
limitations of our higher pressure products are 2500-2700 psig and 125
psig on our lower
pressure electro-mechanical units (provided there is sufficient differential
to create a flow condition through the device).
7) What types of fluids and temperatures can the Flow Matrix accommodate?
a. Flow Matrix devices can be calibrated
for either liquid or gas service. We can accommodate aggressive media such
as acids
and caustics
provided that the
proper materials are utilized. We typically can handle liquids with entrained
air or small particulates provided that this is specified at time of quotation
request. We commonly recommend a standard 5 micron particle filter upstream
for most applications, with exception to special low flow liquids. Standard
temperature
ratings are up to 100∞C for manual devices and 70∞C for electronic
devices. Higher temperature options are available for applications up to
150∞C
for electronic devices and 300∞C for manual devices.
8) What types of materials does Flow Matrix offer?
a. Standard materials include 316 stainless,
brass, and aluminum. Flow Matrix also offers novel materials such as Hastelloy
C and Monel
Alloy 400. Flow Matrix
also offers a wide range of sealing materials such as Buna, Viton, EPDM,
Perfluoroelastomer (Kalrez® equivalent), Neoprene and valve materials such as titanium alloy,
Monel, and Inconel. Valve seat material options include Kel-F® or PEEK.
9) What types of options are available with Flow Matrix devices?
a. Flow Matrix offers manual devices with
knob adjustments, pneumatic devices with electronic pressure control systems
and integrated sensors, fully electronic
units with voltage, current, or digital communications. There are different
product series that come in traditional regulator footprints, MFC footprints,
and the
new ANSI/ISA 76.00.02-2002 (also called NeSSi or ISASP76) modular surface
mount footprint. Flow Matrix also offers the manual units with integrated
gauge or differential
pressure transducers that can be calibrated for flow rate. This enables
users to have a manual set point and an electronic flow feedback signal.
10) What are the fundamental limitations of Flow Matrix technology?
a. The fundamental limitations of Flow Matrix
technology are:
i. Flow Matrix devices cannot necessarily replace pressure regulators. We can
replace regulators that are used for flow control, but Flow Matrix devices do
not regulate pressure, they regulate flow. They do not require regulated or stable
pressure to regulate the flow as do more traditional devices.
ii. Flow Matrix devices cannot control the flow of
two phase flows (gas and liquid) although they will let entrained air pass
through the device without major upset
in most cases.
iii. The stream composition must be specified at the time of order for
mechanical and electronic devices so that they can scale properly for viscosity
and density/specific
gravity issues. Flow Matrix manual devices can normally be switched over
to different stream compositions without difficulty provided that the overall
density and
viscosity differences are relatively small.
iv. Flow Matrix devices cannot handle slurries, heavy
particulates, liquids with viscosities higher than ~30cP (centipoise),
or media that can crystallize or
condense (other than some small amounts of ambient moisture condensation)
under normal operating conditions. Flow Matrix does not handle non-Newtonian
(i.e. non-linear)
fluids such as ketchup, syrup, etc.
v. Flow Matrix devices cannot be used for positive shut-off applications
without the use of a properly rated isolation valve.
For further questions and answers,
you may contact your local-area Flow
Matrix representative or a factory technical
assistance person.
 contact
us | email us
|
